Minimizing formation of internal organic film in conduits for fermented malt beverages



June 21, 1966 M. B. VORDAHL E' IAL N OF INTERNAL ORGANIC FILM IN MINIMIZING FORMATIO CONDUITS FOR FERMENTED MALT BEVERAGES Filed June 21, 1962 IN VE N TORS. MIL TON B. VORDA HL AND HOWARD B. BOMBERGER A Harney United States Patent This invention pertains to coils and other conduits for the cooling, transportation and dispensing of beverages, and particularly, to an improved coil for use in the cooling and dispensing of fermented malt beverages such as beer,fiale and the like.

Fermented malt beverages, such as beer and ale, are commonly transported in kegs from the brewery to the individual locations of consumption, where the kegs are stored for varying periods of time until use. The individual kegs are then connected to a cooling and dispensing apparatus wherein the beverage is forced, under fluid pressure, from the keg, through a cooling coil, to the dispensing outlet.

' It is extremely important, for cleanliness and health reasons, as well as for the maintenance of flavor quality, that all portions of the storage, cooling and dispensing' apparatus be corrosion-resistant and inert with respect to the beverage being handled. Prior efforts to achieve these requirements have resulted in the use of various materials for the construction of cooling coils ciated disadvantages. For example, many of the previously used metals, such as tin and copper, impart deleterious flavor to the beverage. Glass-lined tubing, of course, is quite fragile, the brittle glass lining being easily fractured by even slight mechanical impact, with the consequent danger of extensive corrosion of the underlying metal and the'hazard of entrainment of dangerous glass particles in the dispensed beverage. The plastic materials which have, on occasion, been utilized for these applications, tend to become embrittled and crack upon exposure to low temperatures and over long periods of time. These, and other materials, such as stainless steel and nickel-containing alloys such as Monel metal, form surface oxides which, in contact with aqueous solutions such as fermented malt beverages, hydrate quite extensively, resulting in entrapment and build up, upon the interior Walls of the conduit, of relatively massive organic films deposited from the beverage. The result has been the necessity, in respect to all prior art coils to remove the adherent, ob-jectionable films. Such periodic cleanings, of course, result in loss of use of the equipment and, moreover, are diflicult to thoroughly accomplish. For example, a common practice is to pump through the conduit a slurry comprising a multitude of small glass beads suspended in an aqueous vehicle. Equipment for such cleaning is, in itself, a major cost factor in the maintenance of the beverage storing, cooling and dispensing equipment.

Therefore, it is an object of this invention to provide, in a beverage storage, dispensing and cooling apparatus, an improved cooling and dispensing conduit wherein the tendency to formation of an internal organic film is minimized. i

It is a further object of the invention to provide bever- Thus, metals such as block tin, stainless steel,

age cooling anddispensing apparatus wherein the flavor of the beverage is substantially unaffected over substantially long periods of use of the apparatus.

It is a still further object of the invention tov provide a beverage cooling and dispensing conduit which requires a minimum of maintenance and cleaning and which has an extended useful life. Y

In accordance with the foregoing objects, the invention ,provides, in an apparatus for storing, cooling and dispensing beverages such as fermented malt beverages, a cooling coil and associated conduits constructed of the metal titanium or a base alloy thereof or of another metal having a surface coating of titanium or a base alloy thereof.

The foregoing and other objects will be more fully understood by reference to the following specification and the accompanying drawing wherein:

FIGURE 1 is a front elevational view, partly in crosssection, of one embodiment of a beverage storage, cooling and dispensing apparatus of the general type contemplated for incorporation of the novel cooling and dispensing conduits of the invention.

Referring now to the drawing of FIGURE 1, the numeral 11 designates generally a beverage container or keg of the general type in which fermented malt beverages such beer and 'ale are transported from the brewery to the point of use and consumption. Containers of this sort are generally provided with a top opening for reception of a fitting 12 having depending therefrom a siphon tube 13 which extends to adjacent the bottom of the bottom of the keg 11 for withdrawal of the beverage. The fitting .12 is also provided with a pipe 14, 'connected through the fitting to a valve 16 which, in turn, is connected to a pressurized fluid line -17 through which a gas, such as carbon dioxide, may be introduced into the keg .11 above the surface of the beverage to force the same upwardly through the tube 13 from which the beverage passes, through a pipe 18, through a first beverage control valve 19, and thence through a beverage conducting conduit 2'1. The conduit 21 is connected to a second beverage valve 22, from which the beverage passes, through a connection2-3, mounted in the wall of a cooling and dispensing unit designated generally by the numeral 24.' The latter comprises an outer housing 26 of a suitable-sheet metal and an inner housing 27. The

. space between the outer and inner housings is occupied cooling and dispensing coils, of frequent cleaning of the by a suitable insulating material 28. The interior of the cooling and dispensing unit 24 is substantially filled with a suitable cooling fluid 29, such as water. Immersed in the fluid 29 is a first coil 31 through which a suitable refrigerant may be conducted, as froman entry connection 32, to an exit connection 33. Located inwardly of and the coil 34 being afiixed at a lower extremity thereof to the connection 23 and, at an upper extremity thereof,

to a dispensing nozzle or faucet 36.

In the operation of the device illustrated in FIGURE 1, the keg 11, when placed in suitable position with respect to the cooling and dispensing unit 24, has inserted therein the fitting 12 and associated items 16, 18 and 19, whereupon the conduit 21 is connected to valves 19 and 22. The latter are then opened and the valve 16 is opened thereby admitting pressurized gas, through line 17 to the interior of kegs 11. This thereupon forces the beverage from the keg into the second coil 34 which is immersed in the cooling fiuid 29, and which in turn is cooled by the refrigerant circulating through the first coil 31.

It has been found that cooling coils and associated conduits, constructed of titanium or a titanium base alloy,

or of another structural metal having a coating of titanium or a titanium base alloy, when incorporated in a beverage storage, cooling, and dispensing device such as that illustrated in FIGURE 1, results in unexpectedlysuperior performance. Thus, not only do such coils and conduits exhibit highly superior corrosion resistance to the external environment of the storage and dispensing unit 24 and to the interior environment, i.e., the beverage, but it has been found, in addition, that coils and conduits constructed of the contemplated materials have a quite unexpectedly superior ability to resist the build-up on the interior conduit surfaces of the aforementioned organic scales or films which have been found to present such a disadvantage in the case of prior art coils and conduits. Consequently, beverages such as fermented malt beverages, as beer, ale or the like, dispensed from equipment wherein the novel coils and conduits are incorporated, have the flavor and aroma thereof substantially unaffected over long periods of time. Moreover, the novel coils of the invention require cleaning much less frequently than do coils made of prior art materials.

As aforesaid, most prior art metals, commonly used in the construction of beverage cooling coils and conduits, when exposed to the beverage environment, form oxides of the corresponding metal. Formation of metal oxides on the. interior coil surfaces is desirable since such oxide films are electrically insulative toa more or less great degree, and consequently decrease the electrophoretic drift or movement of suspended, charged, organic particles in the liquid medium under the influence of the voltage gradient which inevitably exists between the moving fluid and the metal wall. These particles, driven by the voltage gradient, tend to deposit upon the metal wall and collect in the form of a film of ever-increasing thickness. Not only does the formation of such film continuously decrease the effective internal diameter of the coil or conduit, but, in addition, the film, being organic in nature, has a distinctly deleterious effect upon the flavor and aroma of the beverage.

Although many prior art materials of construction, such as stainless steel, t'in, copper, Monel metal and the like do form electrically insulating oxide films, the films formed on such metals have the disadvantage of extensively hydrating in the presence of aqueous media such as fermented malt beverages and the like. The films are highly porous or gelatinous and thereby tend to entrap the suspended particles from the beverage and thereby to facilitate the formation of a mechanically objectionable and flavorand aroma-deteriorating organic film inside the coils which, as aforesaid, must be frequently removed by a laborious, expensive and time consuming process in order to maintain the cooling and. dispensing equipment at a top level of operating efliciency and to maintain beverage quality.

In contradistinction to the oxide films formed, as aforesaid, upon prior art materials of construction, it has been found that the oxide films formed on the novel coils and conduits of this invention, constructed from titanium or a base alloy thereof, do not hydrate in the presence of aqueous media. Moreover, the titanium oxide films are highly electrically insulative and thereby minimize or eliminate the voltage gradient between metal Wall and fluid which normally exists in prior art apparatus. Therefore, the oxide films formed on the coils of the invention minimize the formation of wall films due to electrolytic deposition of suspended charged particles. Furthermore, the oxide films on the novel coils are, and remain during the operation of the equipment in which they are incorporated, quite smooth, non-hydrated and non-porous, thereby not only maintaining their electrical insulating character, but also presenting a surface resistant to entrapment and formation of the organic films so objectionable in prior art equipment.

It will be seen, therefore, that the invention provides, in beverage storage, cooling and dispensing devices, coils and conduits of a highly improved character vis-a-vis corrosion resistance, long life, minimal maintenance and maintenance of an enhanced beverage flavor and aroma.

The foregoing specification and drawing are merely illustrative of the principles of the invention and it is to be understood that various other embodiments, modifications and additions may be utilized, practiced and made by those skilled in the art without departing from the spirit and scope of the invention.

What is claimed is:

1. A method of minimizing flavor degradation of a fermented malt beverage during storage, cooling and dispensing thereof, comprising storing, cooling and dispensing the beverage in contact with confining surfaces composed of a material selected from the group consisting of titanium-and titanium base alloys.

2. A method of minimizing the formation of flavordegrading, organic films deposited upon the surfaces of fermented malt beverage cooling and dispensing apparatus, thereby maintaining enhanced flavor quality and e xtending the time between successive cleanings of said apparatus, comprising storing the beverage in contact with and dispensing the same through a tubular metallic cooling coil having at least the interior surfaces thereof composed of a material selected from the group consisting of titanium and titanium base alloys.

References Cited by the Examiner UNITED STATES PATENTS 2,448,462 8/ 1948 Renzoni. 2,644,820 7/ 1953 Gresham. 2,755,199 7/1956 Rossheim et al. l1722 X 2,964,399 12/1960 Lyons 175.5 X

OTHER REFERENCES Everhart, Titanium and Titanium Alloys, pub. by Reinhold Pub. Co., New York, 1954, pp. and 169.

Hind, H. L. Brewing Science and Practice, vol. 2, Secs. 543-549, pub. by Chapman Hall Ltd., London, 1950.

McQuillun et al., Titanium, Butterworth Scientific Publications, London (1956), pp. 94, 428-445.

Reprint from Chemical Week, April 18, 1959, Union Carbide Metals Co.

A. LOUIS MONACELL, Primary Examiner. ABRAHAM H. WINKELSTEIN, Examiner. 

1. A METHOD OF MINIMIZING FLAVOR DEGRADATION OF A FERMENTED MALT BEVERAGE DURING STORAGE, COOLING AND DISPENSING THEREOF, COMPRISING STORING, COOLING AND DISPENSING THE BEVERAGE IN CONTACT WITH CONFINING SURFACES COMPOSED OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF TITANIUM AND TITANIUM BASE ALLOYS. 